With this type of float valve apparatus, for introducing gas and liquid into the valve chamber through the inlet pipe, of the liquid and the gas, the liquid is selectively discharged from the valve chamber through the discharge path, in association with opening/closing of the valve opening by the opening/closing means.
This float valve apparatus includes a foreign object removing member that moves forwardly in the discharge path toward the valve opening so as to remove a foreign object in the discharge path. This foreign object removing member is movable rearward by an operation from the outside of the valve case, thus facilitating a foreign object removing operation when a foreign object becomes stuck or adheres within the discharge path in the course of discharging of the liquid from the valve chamber.
FIG. 10 shows a conventional construction of this type of float valve apparatus (see Patent Document 1 below). Within the valve chamber 2, there is incorporated a float type valve body 7 as an example of the opening/closing means. In operation, as this float valve body 7 is seated on or detached from a valve seat forming the valve opening 6a, in association with movements of the float member as floating in the liquid introduced into the valve chamber 2, so that the valve body functions as a valve opening opening/closing portion at its outer surface to close/open the valve opening 6a. The foreign object removing member 8 is inserted in sliding contact to an insertion hole 5a formed in a wall portion of the valve case 5. Further, at an intermediate portion of the foreign object removing member 8, there is formed a retraction stopper 8e in the form of a flange. This retraction stopper 8e comes into contact with an outer peripheral edge of the insertion hole 5a in the inner face of the wall portion of the valve case 5, thereby to restrict a retracting movement of the foreign object removing member 8. Further, at a rear end of the foreign object removing member 8, there is formed a spring receiving portion 8f. And, between this spring receiving portion 8f and the wall outer face of the valve case 5, there is incorporated a compression spring 18.
With this float valve apparatus, by an urging force provided by the compression coil spring 18, the foreign object removing member 8 is urgedly retained at a retracted position where the movement of the member is restricted by the retraction stopper 8e. When an operator pushes the foreign object removing member 3 further into the insertion hole 5a formed in the valve case 5 against the urging force of the compression coil spring 18, the foreign object removing member 8 is moved forward or advanced in the discharge path 4 to extend through the valve opening 6a. 
When a foreign object gets stuck in the discharge path 4, the operator will momentarily push the foreign object removing member 8 urged to the retracted position by the compression coil spring 18. With this, the foreign object removing member S is advanced to remove the foreign object in the discharge path 4. After the removal of the foreign object, under the urging force of the compression coil spring 18, the foreign object removing member 8 will be instantaneously returned to the retracted position. This is the conventional cleaning method for removing a foreign object in the discharge path 4.    Patent Document 1: Japanese Utility Model Published Sho. 49-36747